Interesting video. It made me think, though, of the quote by Mark Twain: "There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact.”

I would certainly be slow to make such grand announcements (as the author of the blog site did) of proving this or that with this experiment. Other options sound more plausible to me. Like, if you place the bacteria next to a low dose of the chemical, they can build immunity to the toxin. Like getting a measles shot vs. being stuck straight into a room full of measles patients.

If this was "random genetic" changes as proposed, one would not need to start with a low dose, because the random change could just as likely be a change that could handle 10, 100, or 1000 potency ... if it was random. And, if one placed other toxic substances next to the bacteria (acidic, saline, h202, or even heat), then within two weeks random mutations would also just as likely happen to let the bacteria grow in that toxin.
But it appears that this experiment can only be replicated using this specific strain with one specific toxin. That leads me to conjecture that this is not "random mutations" but a built-in immunity that the species (or at least some strains or specimens) kick in when needed ... if they are given the right conditions.

But wait, what was Twain saying about "wholesale returns of conjecture"?

I think I will return now to my current issue of trying to get a decent photo out of my microscope.